Dual functional robot and storage bin

ABSTRACT

A dual functional robot for collecting rollable objects capable of an upright position and a horizontal position, in which the robot includes a way to propel the robot; a way to control propulsion of the robot; a way to locate the rollable object; a way to collect the rollable object; a way to store the rollable object; a way to support the robot and allow the robot to move across a surface in a low-friction manner; and a way to stably reorient the robot from the horizontal position into the upright position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation under 35 U.S.C. 120 of U.S. patentapplication Ser. No. 14/985,020, filed 30 Dec. 2015. U.S. patentapplication Ser. No. 14/985,020 claims the benefit of U.S. ProvisionalApplication No. 62/120,855, filed 25 Feb. 2015, and U.S. ProvisionalApplication No. 62/210,461, filed 27 Aug. 2015. The contents of all ofthe foregoing applications are incorporated herein by reference in theirentireties, although the prosecution histories of the foregoing are notincorporated by reference.

BACKGROUND A. Field of the Disclosure

The present disclosure relates generally to robots, and moreparticularly to an autonomous robot for collecting rollable objects anda method for collecting rollable objects.

B. Background

The sport of tennis is a popular and growing activity that attractsmillions of participants each year. To improve their skills, tennisplayers frequently engage in practice drills using a machine or anotherperson. To save time and effort, players often have a large number oftennis balls so that the player may continue to practice withoutconstantly retrieving tennis balls. Although additional balls improvethe player's efficiency during practice, the player must later engage inthe tedious task of collecting the tennis balls after the practicesession.

Similar problems exist in other sports and activities using balls orother handheld objects.

Several devices have been offered to improve the process of collectingtennis balls. Early devices were hand operated and required the playerto push the device around the tennis court to collect the balls.Although these devices lessened the burden on the player, the devicesstill required that the player participate in the collection of theballs.

Robotic collectors have been attempted, but none have been light enoughand energy-efficient enough for widespread public acceptance. Althoughsuch devices allow the player to rest while the device collects theballs, the devices suffer from numerous defects. First, such devices donot provide a convenient method for players to use the balls aftercollection. Although such devices use various means to lift and storethe ball at a height convenient for later use, these means requiresignificant power to lift tennis balls and would therefore quicklydeplete the energy source. As a result, the player must take additionalsteps after collection to make convenient use of the balls. Second, suchdevices are not energy efficient. Such devices deploy collectionmechanisms that use significant energy to collect the balls, whichrequires either that the player frequently charge the device or that thesystem incorporate large, heavy energy sources. In addition, suchdevices do not necessarily use efficient algorithms for ball location,resulting in the device wasting energy by travelling in inefficientcollection patterns.

Consequently, there is a long-felt need in the art for an efficient,light-weight, autonomous ball collection device that provides convenientaccess to balls after collection.

SUMMARY

The problems in the art described above are addressed by the robots andmethods provided in this disclosure. Although the identified problemsare described in the context of the collection of tennis balls, itshould be recognized that similar problems apply generally to thecollection of rollable objects and that the robots and methods taughtherein are generally applicable to the collection of other rollableobjects.

An autonomous robotic rollable object collector is provided. A generalembodiment of the robot comprises: (a) a center of mass, a front end, arear end, a midpoint, and an axis of rotation, wherein the center ofmass is between the front end and the midpoint, and the axis of rotationis the axis about which the robot rotates when tilted between theupright position and the horizontal position; (b) a first load-bearingwheel supporting the robot forward of the midpoint, having a radius (r),positioned so that the robot in the horizontal position may be rotatedat least 45° along the axis of rotation without the front end cominginto contact with the ground; (c) a mobile load-bearing supportstructure supporting the robot rearward of the midpoint while in thehorizontal position; (d) a drive motor providing rotation to a drivewheel; (e) an energy source providing energy to the drive motor; (f) arotating collector proximate to the front end; (g) a holding baskethaving a first basket position, in which said holding basket ispositioned to receive the rollable object from the rotating collectorwhile in the horizontal position and in the first basket position; (h) acontroller connected to provide control signals to the drive motor; and(i) a sensor connected to provide data to the controller. In thisgeneral embodiment, the robot is capable of a upright position and ahorizontal position. The robot autonomously collects rollable objectswhen in the stable horizontal position. After the robot collects theobjects, the user can easily tilt the robot into the stable uprightposition, which elevates the position of the collected balls to allowconvenient access.

Another general embodiment of the robot comprises: (a) means forpropelling the robot; (b) means for controlling propulsion of the robotconnected to provide commands to the means for propelling; (c) means forlocating the rollable object connected to provide data to the means forcontrolling propulsion; (d) means for collecting the rollable object;(e) means for storing the rollable object positioned to accept therollable object from the means for collecting; (f) means for supportingthe robot and allowing the robot to move across a surface in alow-friction manner; and (g) means for stably reorienting the robot fromthe horizontal position into the upright position.

A method for collecting a plurality of rollable objects is alsoprovided. The method comprises: (a) providing either of the robotsdescribed above; (b) geofencing a collection area to establishboundaries of the collection area; (c) instructing the controller toscan the collection area with the sensor; (d) querying the sensor as towhether one of the plurality of rollable objects has been located; (e)determining whether said one of the plurality of rollable objects islocated within the boundaries of the collection area; and (f) if saidone of the plurality of rollable objects is located within theboundaries of the collection area, instructing the controller to directthe robot to said one of the plurality of rollable objects and collectsaid one of the plurality of rollable objects, and if not instructingthe controller to continue scanning the collection area with the sensor.According to this method, the robot efficiently collects the pluralityof rollable objects. By only collecting the rollable objects in theboundaries of the collection area, the robot conserves time and energyin the collection process.

The above presents a simplified summary in order to provide a basicunderstanding of some aspects of the claimed subject matter. Thissummary is not an extensive overview. It is not intended to identify keyor critical elements or to delineate the scope of the claimed subjectmatter. Its sole purpose is to present some concepts in a simplifiedform as a prelude to the more detailed description that is presentedlater.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1: A side view of an envisioned embodiment of the robot in thehorizontal position.

FIG. 2: A perspective view of the embodiment of the robot shown in FIG.1 in the upright position.

FIG. 3: An exploded view of the embodiment of the robot shown in FIG. 1.

FIG. 4: A detailed view of the front end and the first load-bearingwheel of the embodiment of the robot shown in FIG. 1.

FIG. 5: A perspective view of the embodiment of the robot shown in FIG.1 in the upright position with the chassis in the extended chassisposition.

FIG. 6: A block diagram of an embodiment of the method for collectingrollable objects.

DETAILED DESCRIPTION A. Definitions

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art of this disclosure. It will be furtherunderstood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the specification andshould not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein. Well known functions or constructions maynot be described in detail for brevity or clarity.

It will be understood that when a feature or element is referred to asbeing “on” another feature or element, it can be directly on the otherfeature or element or intervening features and/or elements may also bepresent. In contrast, when a feature or element is referred to as being“directly on” another feature or element, there are no interveningfeatures or elements present. It will also be understood that, when afeature or element is referred to as being “connected”, “attached” or“coupled” to another feature or element, it can be directly connected,attached or coupled to the other feature or element or interveningfeatures or elements may be present. In contrast, when a feature orelement is referred to as being “directly connected”, “directlyattached” or “directly coupled” to another feature or element, there areno intervening features or elements present. Although described or shownwith respect to one embodiment, the features and elements so describedor shown can apply to other embodiments.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a”, “an” and “the” are intended to include the pluralforms as well (i.e., “at least one”), unless the context clearlyindicates otherwise.

Spatially relative terms, such as “under”, “below”, “lower”, “over”,“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another when the robotis positioned in the horizontal position (i.e., right side up).

The terms is “first” and “second” are used herein to describe variousfeatures or elements, but these features or elements should not belimited by these terms. These terms are only used to distinguish onefeature or element from another feature or element. Thus, a firstfeature or element discussed below could be termed a second feature orelement, and similarly, a second feature or element discussed belowcould be termed a first feature or element without departing from theteachings of the present disclosure.

With reference to the use of the words “comprise” or “comprises” or“comprising” in the foregoing description and/or in the followingclaims, unless the context requires otherwise, those words are used onthe basis and clear understanding that they are to be interpretedinclusively, rather than exclusively, and that each of those words is tobe so interpreted in construing the foregoing description and thefollowing claims.

The term “consisting essentially of” means that, in addition to therecited elements, what is claimed may also contain other elements(steps, structures, ingredients, components, etc.) that do not adverselyaffect the operability of what is claimed for its intended purpose asstated in this disclosure. This term excludes such other elements thatadversely affect the operability of what is claimed for its intendedpurpose as stated in this disclosure, even if such other elements mightenhance the operability of what is claimed for some other purpose.

The terms “about” or “approximately” mean within a range of reasonableerror around a central value. Such reasonable error may for example stemfrom the precision of an instrument or method used to measure the value.The error could also stem from the precision of a method of making acomponent of a device. Specific examples of such limits of reasonableerror are 20%, 10%, 5%, 2.5%, and 1%. Unless specified otherwise, allnumerical values in the specification are approximate. Unless specifiedotherwise, all numerical values in the claims are exact.

B. Robot

An autonomous robotic rollable object collector 110 is provided. Therobot 110 is capable of a horizontal position 111 and an uprightposition 211. In the horizontal position 111, the robot 110 is capableof autonomously collecting a rollable object. The rollable object may bea tennis ball, a golf ball, or any other spherically shaped object.Alternatively, the rollable object may be of a different shape having acircular, elliptical, or oval cross-section; for instance a cylindricalshape, conical shape, etc., so long as it is capable of rolling on asurface.

A general embodiment of the robot 110 comprises: (a) a center of mass128, a front end 112, a rear end 114, a midpoint 116, and an axis ofrotation, wherein the center of mass 128 is between the front end 112and the midpoint 116, and the axis of rotation is the axis about whichthe robot 110 rotates when tilted between the upright position 211 andthe horizontal position 111; (b) a first load-bearing wheel 118supporting the robot forward of the midpoint 116, having a radius (r),positioned so that the robot 110 in the horizontal position may berotated at least 45° along the axis of rotation without the front end112 coming into contact with the ground; (c) a mobile load-bearingsupport structure 120 supporting the robot 110 rearward of the midpoint116 while in the horizontal position 111; (d) a drive motor 310providing rotation to a drive wheel 130; (e) an energy source 312providing energy to the drive motor 310; (f) a rotating collector 314proximate to the front end 112; (g) a holding basket 122 having a firstbasket position 123, in which said holding basket is positioned toreceive the rollable object from the rotating collector 314 while in thehorizontal position 111 and in the first basket position 123; (h) acontroller 318 connected to provide control signals to the drive motor310; and (i) a sensor 126 connected to provide data to the controller318.

Referring now to the drawings, FIG. 1 provides a side view of oneembodiment (referred to herein as the “envisioned embodiment”) of therobot 110 in the horizontal position 111 and FIG. 2 provides aperspective view of the envisioned embodiment of the robot 110 in theupright position 211. As shown in FIG. 1, the robot generally has afront end 112, a rear end 114, and a midpoint 116. Two firstload-bearing wheels 118 are attached to the robot 110 forward of themidpoint 116, and a pair of mobile load-bearing support structures 120are attached rearward of the midpoint 116. In the envisioned embodiment,the mobile load-bearing support structures 120 comprise a pair of secondload-bearing wheels. But in alternative embodiments, the mobileload-bearing support structure may comprise one or more otherstructures, such as a skid, a caster, or a roller. The firstload-bearing wheel 118 and the second load-bearing wheel 120 may beconstructed of any suitable material. Although the first load-bearingwheel 118 is shown having a radius substantially greater than the secondload-bearing wheel 120, it is understood that the wheels 118, 120 may beof any suitable radius. In general, however, it is preferred that thefront wheel 118 have a larger radius to facilitate the transition of therobot 110 from the horizontal position 111 to the upright position 211.Although wheels are provided in the envisioned embodiment, the robot mayuse other means to support the robot and allow it to move across asurface in a low-friction manner. For instance, a track drive system maybe used. As another example, rollers may be used, particularly for aload-bearing wheel that is not a drive wheel.

As illustrated in the figures, in some embodiments of the robot 110there are a plurality of first load-bearing wheels 118 and/or aplurality of mobile load-bearing support structures 120. Specificembodiments of the robot comprise two first load-bearing wheels, twomobile load-bearing support structures, or both. In embodiments of therobot with more than one first load-bearing wheel 118, the firstload-bearing wheels may be co-axial. The load-bearing wheels may also bedrive wheels 130. Embodiments of the robot 110 in which the first(front) load bearing wheel 118 is a drive wheel have the advantage offacilitating the location of the drive motor 310 in the front 112 of therobot, which creates a lower center of mass 128 when the robot is in theupright position 211 due to the generally high mass of drive motors 310.It also allows the robot 110 to be steered by simply providing differingamounts of power to the drive wheels 130.

The drive wheel 130 may be the same as any of the load-bearing wheels118, 120. There may of course be multiple drive wheels 130. A specificembodiment of the robot comprises two first load-bearing wheels 118which are also the two drive wheels 130. Alternatively, where the mobileload-bearing support structure 120 is a second load-bearing wheel 120,the second load-bearing wheel may be the drive wheel. Of course, thedrive wheel may also be a non-load bearing wheel, so long as the robothas load bearing wheels and mobile load-bearing support structures insufficient number and strength to support it.

The envisioned embodiment of the robot 110 in FIG. 1 also includes anoptional housing unit 124 and a holding basket 122. The housing unit 124contains a drive motor, an energy source, a rotating ball collector, anda controller. The housing unit 124 may be constructed of any suitablematerial, such as a plastic like high density polyethylene or a metalalloy. In alternative embodiments, the robot 110 may not include ahousing unit 124, or the drive motor, the energy source, the rotatingcollector, or the controller may be located outside of the housing unit.A sensor 126 is attached to the top of the housing unit 124 and iscapable of detecting the rollable object. The sensor 126 mayalternatively be attached at any location on the robot 110 that issuitable for detecting the rollable object, and in some embodiments, therobot may include more than one sensor 126 for detecting the rollableobject.

The holding basket 122 contains the rollable object collected by therobot 110, and FIG. 1 shows the holding basket 122 in a first basketposition 123. In the first basket position 123, the holding basket 122is positioned to receive the rollable object from the rotatingcollector. The holding basket 122 may be any suitable shape, such as arectangular prism or a cylindrical prism, and constructed of anysuitable material, such as a plastic or a metal alloy. Alternatively,the robot may use other means for storing the rollable object, such as asack. Some embodiments of the basket are reversibly removable from therobot, to allow a user to carry the loaded basket to another location tobe emptied, and then returned to the robot.

The robot 110 has a center of mass 128. Although components like thedrive motor and the energy source may be attached in various locationson the robot 110, the components must be attached such that the centerof mass 128 is located at some point between the front end 112 and themidpoint 116. By maintaining a center of mass 128 between theselocations, the robot 110 may be more easily transitioned between thehorizontal position 111 and the upright position 211. Furthermore, therobot 110 is more stable in the upright position 211 due to a lowercenter of mass 128.

The envisioned embodiment is shown in the upright position 211 in FIG.2. The upright position 211 is an orientation of the robot which hasbeen tilted at least 45 degrees upward from the horizontal position 111.The robot 110 has an axis of rotation, which is defined as the lineabout which the robot 110 rotates when it is tilted between thehorizontal position 111 and the upright position 211. In a specificembodiment of the robot, the axis of rotation of the robot is coaxialwith the load bearing wheel's axis of rotation. The upright position 211allows more convenient access to the rollable objects because the heightof the holding basket 122 is elevated. When the envisioned embodiment ofthe robot 110 is in the upright position 211 as shown in FIG. 2, it issupported by the first load-bearing wheel 118. The robot may beoptionally supported by at least one additional load-bearing supportstructure 212, 214. The envisioned embodiment of the robot 110 shows twotypes of load-bearing support structures 212, 214. The support structure212 is proximate to the front end 112 and positioned to contact theground when the robot 110 is in the upright position 211. For instance,as shown in FIG. 2, the housing unit 124 may include a surface 212 thatcontacts the ground when the robot 110 is in the upright position 211.Alternatively or additionally, the robot 110 may include a retractablestrut 214. The retractable strut 214 has a retracted strut position 215and an extended strut position 515. The retractable strut 214 is ofsufficient length to contact the ground when the robot 110 is in theupright position 211 and the retractable strut 214 is in the extendedstrut position 515. As envisioned in the embodiment of FIG. 2, theretractable strut 214 is a folding leg, but it should be understood byone skilled in the art that other types of retractable struts may beused. For instance, a retractable strut may comprise a kickstand,similar to a kickstand typically found on a bicycle. A kickstand has theadvantage of allowing a user to deploy the stand using only the user'sfeet, so that the user does not need to bend down to deploy it.Regardless of its precise structure, the load-bearing support structure212, 214 helps to stabilize the robot 110 in the upright position byproviding an additional point of contact with the ground.

As shown in FIG. 2, some embodiments of the robot include an optionalchassis 216. The chassis 216 may be an extendable chassis, having anextended chassis position 517 and a retracted chassis position 217. Thechassis 216 may be constructed of any suitable material, such as a metalor a plastic, and may use any method of extension that is known by thoseskilled in the art. For instance, the chassis 216 may comprise atelescoping member that allows the chassis 216 to extend to the extendedchassis position 517. Alternatively, the robot 110 may not include achassis 216, but may use other known means to reversibly extend theheight of the robot 110 when the robot is in the upright position 211.For instance, the robot 110 may have an extendable body.

FIG. 3 provides an exploded view of the envisioned embodiment of therobot 110. The robot 110 generally has at least one first load-bearingwheel 118 and at least one mobile load-bearing support structure 120. Asdiscussed with respect to FIG. 1, the housing unit 124 contains thedrive motor 310, the energy source 312, the rotating collector 314, andthe controller 318. The drive motor 310 provides rotation to the drivewheel 130. The drive motor 310 may use any method or combination ofmethods to provide rotation that is known in the art, such as byconnecting directly to the wheel, connecting through gears to the wheel,or connecting by a belt to the wheel. In the envisioned embodiment, thedrive motor 310 comprises an electrical motor. In alternativeembodiments, the drive motor 310 may comprise a combustion engine, apneumatic motor, a hydraulic motor, or any other suitable means forpropelling a robot that is known in the art.

The energy source 312 is connected to provide energy to the drive motor310. The energy source 312 may comprise any suitable source of energy.For instance, a rechargeable battery, such as a lithium-ion battery, maybe used for an electrical motor. Alternatively, a disposable battery,such as one or more lithium batteries, may be used. The energy source312 may also comprise a fuel cell. In yet other embodiments, the energysource 312 may comprise a source of alternating current. For instance,the energy source 312 may be a conventional power cord connected to apower outlet that is connected to an electrical grid. The energy source312 may also comprise a source that wirelessly provides energy, such asthrough the use of an electromagnetic field. In embodiments using acombustion engine, the energy source 312 may comprise gasoline, diesel,propane, or any other suitable fuel for combustion. And in embodimentswith a compressed air motor, the energy source 312 may comprise anysuitable compressed gas that may be stored in a container, such as atank.

The rotating collector 314 is attached proximate to the front end of therobot 110 and provides means for collecting the rollable objects. In theembodiment shown in FIG. 3, the rotating collector 314 comprises aplurality of blades connected to a shaft, and it may be constructed ofany suitable material, such as a plastic or a metal alloy. Variousstructures may provide rotation to the rotating collector 314. In someembodiments, the robot may include a second drive motor to providerotation to the rotating collector 314. The second drive motor be anyknown suitable motor, including for example an electric motor, acombustion engine, a pneumatic motor, or a hydraulic motor. The secondmotor may be connected to receive energy from a separate energy source,such as a battery or a fuel cell, or it may be connected to the energysource 312 that provides energy to the drive motor 310. In otherembodiments, the drive motor 310 may provide rotation to the rotatingcollector 314. Alternatively, the rotating collector may be rotated bythe movement of the robot. For instance, the rotating collector may beconnected to a wheel that turns when the robot moves forward. To receivethe rotational force, the rotating collector 314 may be connected usingany suitable structure, such as a drive belt or a plurality of gears. Asshown in FIG. 3, when the shaft rotates, any blade near the front willrotate towards the rear by traveling downward, and any blade near therear will rotate towards the front by traveling upward. In someembodiments, the robot 110 includes a ramp 316, which may be optionallylocated in the housing unit 124. The ramp 316 is positioned to receivethe rollable object from the rotating collector 314 and guide therollable object to the holding basket 122 in the first basket position123. Thus, in the envisioned embodiment, when the robot 110 approachesthe rollable object, the rotating collector 316 will propel the rollableobject toward the rear end 114 and up the ramp 316. The ramp 316 willguide the rollable object into the holding basket 122, where therollable object is then stored. The combination of the blade-and-shaftcollector and ramp provides a low energy means to collect and hold theobjects, as the objects are elevated only a short distance beforefalling off the end of the ramp. In some embodiments of the robot therotation of the collector is selectively activated when the robot is inclose proximity to an object to be collected, which also serves toconserve power. In other embodiments, the rotating collector may be ofdifferent structures. For instance, the rotating collector 314 maycomprise a roller with a high-friction surface, such as a rubbersurface. In such embodiments, the rotating collector rotates such that,when the high-friction surface of the roller contacts the rollableobject, the rollable object is propelled toward the rear end 114 andinto the holding basket 122. The roller may be as simple as a cylinder,or may have a generally cylindrical shape. In other embodiments, therotating collector 314 may comprise a rotating belt assembly to lift therollable object into the holding basket 122. The rotating collector 314may also comprise a shaft that is perpendicular to the ground with aplurality of blades connected thereto, where the shaft and the bladesrotate to propel the rollable object into the holding basket 122. Aswill be recognized by one skilled in the art, the robot may also employother means for collecting the rollable object, such as a suctionsystem.

The envisioned embodiment of the robot 110 has a controller 318 toprovide means for controlling the propulsion of the robot 110. Thecontroller 318 may comprise a microcontroller, which typically containsa processor core, memory, and programmable input/output peripherals.Alternatively, the controller 318 may comprise a microprocessor, and themicroprocessor may optionally include peripheral devices such as amemory or a transceiver. The controller 318 connects to the sensor 126to receive data from the sensor 126 and connects to the drive motor 310to provide control signals to the drive motor 310. For instance, whenthe sensor 126 provides data that locates a rollable object, thecontroller 318 provides control signals to the drive motor 310 to directthe robot 110 to the rollable object. The controller 318 mayalternatively be located outside of the housing unit 124, and it mayconnect to the sensor 126 and the drive motor 310 using any acceptablemeans, such as a wired connection or a wireless connection. Thecontroller 318 has access to logic for processing the sensor data tolocate the rollable objects. In the envisioned embodiment, thecontroller 318 contains this logic, which may be programmed logic to beexecuted by the processor or hardwired logic. But the logic may beoptionally stored and executed on other devices. For instance, in someembodiments, the controller 318 may comprise a hardware unit thatreceives data from the sensor 126; transmits the data to a remoteprocessing unit, such as a remote computer; and receives commands fromthe remote processing unit. In such an embodiment, the remote processingunit would receive the data transmitted by the controller 318, apply thelogic to the data, and provide command signals to the controller 318.

Referring again to FIG. 3, the envisioned embodiment of the robot 110has two sensors 126. More specifically, the sensors 126 are visualsensors that are positioned to provide overlapping fields of view. Thevisual sensor may comprise a photodetector, which may be similar to thephotodetector often in cell phone cameras or web cameras. The visualsensor may also comprise an infra-red sensor. In alternativeembodiments, the sensor 126 may not be a visual sensor. Instead, thesensor 126 may comprise a sonar system, which may emit sound to locatethe rollable objects. Other embodiments may have a sensor 126 thatdetects radio frequency identifications (RFIDs). In such an embodiment,the rollable objects may each contain an RFID tag that can be detectedby the sensor 126. The sensors 126 in the envisioned embodiment detectrollable objects based on the color of the rollable object anddetermines the distance of the rollable object by comparing its knownsize to its perceived size. The sensors 126 are connected to thecontroller 318 to provide data to the controller 318, such as thelocation of the rollable object. The sensors 126 may be connected usingany suitable type of connection, such as a wired connection or awireless connection. However, it would be recognized by one skilled inthe art that the sensor 126 may employ other methods to detect anddetermine the location of the rollable object, such as by comparingdifference in the perceived positions of the object in the twooverlapping fields of view. The use of stereo images to determine thelocation of the object has the advantage of being capable of locating anobject of unknown size (i.e., it does not depend on the perceived sizeof the object to calculate distance). Alternatively, a robot 110 mayinclude only one sensor, more than two sensors 126, or other means tolocate the rollable objects.

FIG. 4 provides a detailed view of the front end 112 and the firstload-bearing wheel 118. The front end 112 has a bottom surface 410 whenthe robot is in the horizontal position 111. The first load-bearingwheel 118 has a radius (r) and an axis, which may correspond to therobot's axis of rotation where, as in this embodiment, the firstload-bearing wheels are co-axial. The first load-bearing wheel ispositioned so that the robot 110 may be rotated at least 45° about theaxis of rotation from the horizontal position without the front end 112coming into contact with the ground. The bottom surface 410 of the frontend 112 therefore must have sufficient clearance while in the horizontalposition to allow the robot 110 to be rotated on the load-bearing wheel118 between its two positions. The clearance distance is measured as thedistance between the bottom surface 410 and the ground when the robot isin the horizontal position 111. To allow the robot 110 to be rotated atleast 45°, the bottom surface 410 must have a clearance distance (C) atevery distance (h) in front of the axis of rotation, such thatC≥h+r*[1−sqrt(2)]  Formula 1In embodiments in which the clearance distance (C) is not consistentacross the bottom surface 410 at a given distance (h) in front of theaxis, formula 1 above would be applied to the smallest C (leastclearance) at the given h. This formula is graphically depicted as aline in FIG. 4. By requiring that no point on the robot 110 extendbeyond the line, it is ensured that the robot may be tilted at least 45degrees along its first load-bearing wheel 118. In alternativeembodiments, the robot 110 may use other means, such as a roundedsurface proximate to the front end 112, to allow for the stablereorientation of the robot from the horizontal position to the uprightposition. Alternatively, the load-bearing wheel 118 could be positionedin front of the front end 112. It is to be understood that the “bottomsurface” need not be one continuous surface, but may be a plurality ofsurfaces or structures that define the lowermost structures of the frontend.

FIG. 5 provides a perspective view of the envisioned embodiment of therobot 110 in the stable upright position 211 with the chassis 216 in theextended chassis position 517 and the retractable strut 214 in theextended strut position 515. Furthermore, FIG. 5 shows the holdingbasket 122 in a second basket position 523, which is higher than thefirst basket position 123 when the robot is in the upright position 211.The holding basket 122 may be elevated using various means. Forinstance, if the robot 110 includes a chassis 216 with a telescopingmember, the holding basket 122 may be attached to the telescoping membersuch that the holding basket 122 moves with the telescoping member whenthe chassis 216 is extended to the extended chassis position 517.Alternatively, the holding basket 122 may be movably connected to theextendable chassis 216. For instance, the basket may be movably attachedto the chassis using plastic clips or removable clamps. In such anembodiment, after the extendable chassis 216 is in the extended chassisposition 517, the holding basket 122 may be moved such that the holdingbasket 122 is connected closer to the rear end 114. In yet anotherembodiment, the chassis 216 is not extendable but runs fromapproximately the front end 112 to approximately the rear end 114. Theholding basket 122 may be slidably attached to the chassis 216, whichallows the holding basket to be slid from the first basket position 123to the second basket position 523 proximate to the rear end 114. Theslidable attachment may comprise, for example, a sleeve which fitsaround the chassis 216 and may be slid along the chassis 216, theholding basket 122 being connected to the sleeve. As one skilled in theart will recognize, other known means may be used to extend the heightof the robot 110 and to elevate the holding basket 122 when in theupright position 211.

In some embodiments, the holding basket 122 is at least about 80 cm fromthe ground when the robot 110 is in the upright position 211 and theholding basket 122 is in the second basket position 517. In furtherembodiments, the holding basket 122 is at least about 100 cm from theground when the robot 110 is in the upright position 211 and the holdingbasket 122 is in the second basket position 517. The distance from theholding basket 122 to the ground is measured from the ball supportingsurface of the holding basket 122 when the robot 110 is in the uprightposition 211. At this height, the robot 110 provides an adult withconvenient access to the rollable objects in the holding basket 122.This convenience is provided because the height of at least about 80 cmapproximately corresponds with the hand level of most adults whenstanding. For instance, a tennis player would be able to retrieve tennisballs from the holding basket 122 without bending over once the holdingbasket 122 is in the second basket position 517. This provides a meansto raise the collected objects within reach of a standing user withoutconsuming any power provided by the energy source.

Another general embodiment of the robot comprises: (a) means forpropelling the robot; (b) means for controlling propulsion of the robotconnected to provide commands to the means for propelling; (c) means forlocating the rollable object connected to provide data to the means forcontrolling propulsion; (d) means for collecting the rollable object;(e) means for storing the rollable object positioned to accept therollable object from the means for collecting; (f) means for supportingthe robot and allowing the robot to move across a surface in alow-friction manner; and (g) means for stably reorienting the robot fromthe horizontal position into the upright position.

These means may be the structures described above, or they may be otherstructures. For instance, the means for propelling the robot may be anyversion of the drive motor 310 and the drive wheel 130 described above.The means for propelling may also be any equivalent to these structures,such as a track system connected to a drive system to rotate the tracks,or a plurality of legs connected to actuators to provide movement to thelegs. These means may be connected to any suitable energy sourcedescribed above, such as a battery, fuel cell, or combustible fuel.

The means for controlling the propulsion of the robot may be any versionof the controller 318 described above. The controller 318 is connectedto provide commands to the means for propelling. As described above, themeans for controlling the robot may comprise a remote control source anda receiver, where the remote control source determines the propulsion ofthe robot and provides command signals to the receiver, which transmitsthose signals to the means for propelling.

The means for locating the rollable object may be any version of thesensor 126 described above, such as a visual sensor. The sensor providesdata, such as visual images, to the means for controlling. In someembodiments of the robot, the rollable objects may contain trackerswhich transmit their locations to a receiver on the robot. The receivermay then provide this data to the means for controlling propulsion.

The means for collecting the rollable object may comprise any version ofthe collector 314 described above. Some embodiments of the means forcollecting are any version of the rotating collector 214 describedabove. Alternatively, the means for collecting may be a suction systemthat uses a pressure differential to collect the rollable object, ascoop that lifts the rollable objects, or a claw that grasps therollable objects.

The means for storing the rollable object may be any version of theholding basket 122 described above. In other embodiments, the means forstoring may be a sack, a rack, or a tube.

The means for supporting the robot and allowing the robot to move acrossa surface in a low friction manner may comprise a plurality of wheels118, 120. For example, the means for supporting the robot and allowingthe robot to move across a surface in a low friction manner may be anyversion of the first load-bearing wheel described above, the mobileload-bearing support structure described above, or a combination ofboth. Alternatively, the means may be a plurality of skids, a tracksystem, a plurality of casters, a plurality of rollers, or a pluralityof legs. In some embodiments, the means may comprise multiplestructures. For instance, the means for supporting the robot andallowing the robot to move may comprise a plurality of wheels and aplurality of skids.

The means for stably reorienting the robot from the horizontal positionto the upright position may be any version of the first load-bearingwheel 118 described above. The robot may use other means for stablyreorienting the robot, such as a rounded surface proximate to the frontend. The rounded surface may be part of the body of the robot, thehousing unit, or another structure attached to the robot. In embodimentsusing a track system as a means for supporting the robot, the tracksystem may provide a means for stably reorienting the robot.

The robot may optionally have means to reversibly extend the height ofthe robot when the robot is in the upright position. For instance, themeans for reversibly extending the height of the robot may be anyversion of the extendable chassis 216 described above. In otherembodiments, the means for reversibly extending may be an extendablebody. Alternatively, a component of the robot, such as the means forstoring, may be slidably attached such that the position of the meansfor storing may be raised when the robot is in the upright position,thereby extending the height of the robot.

The robot may also optionally have means to elevate the means forstoring when the robot is in the upright position. For example, themeans may be any version of the extendable chassis 216 with atelescoping member described above, where the means for storing isattached to the telescoping member such that the means for storing israised when the telescoping member is extended. In other embodiments,the means for storing may be slidably or movably attached to the robotsuch that the means for storing may be slid or moved to a heightenedposition when the robot is in the upright position. Additionally, themeans for elevating may include a structure, such as a gas spring, toelevate the means for storing.

C. Method for Collecting Rollable Objects

A method for collecting a plurality of rollable objects is alsoprovided, in which the method uses any of the robots described above.The method comprises: (a) providing the robot as described above 610;(b) geofencing a collection area to establish boundaries of thecollection area 612; (c) instructing the controller to scan thecollection area with the sensor 614; (d) querying the sensor as towhether one of the plurality of rollable objects has been located 616;(e) determining whether said one of the plurality of rollable objects islocated within the boundaries of the collection area 618; and (f) ifsaid one of the plurality of rollable objects is located within theboundaries of the collection area, instructing the controller to directthe robot to said one of the plurality of rollable objects and collectsaid one of the plurality of rollable objects 620, and if notinstructing the controller to continue scanning the collection area withthe sensor 622.

Referring to FIG. 6, the method uses one of the robots 110 describedabove. A collection area must be geofenced to establish the boundariesof the collection area 612. Geofencing refers to the process of definingthe geographical boundaries of an area. The boundaries of the area maybe defined with reference to a global positioning system (GPS), a radiofrequency identification (RFID), or any other technique known in theart. For instance, a user may define the boundaries by using mappingsoftware, such as Google Earth, or providing coordinates from a GPS. Inother instances, the robot 110 may be programmed to define theboundaries of the collection area itself, such as by detecting knownfeatures that define the boundaries.

The controller 318 is then instructed to scan the collection area withthe sensor 614 and the sensor 126 is queried to determine whether thesensor 126 has located one of the plurality of rollable objects 616. Aspreviously discussed, the sensor 126 may use any number of techniquesknown by those skilled in the art to scan the collection area and locatethe rollable objects.

If one of the plurality of rollable objects has been located, it isdetermined whether the rollable object is located within the boundariesof the collection area 618. Various methods may be used to determinewhether the rollable object is located within the boundaries. Aspreviously discussed, the sensor 126 may determine the distance of therollable object from the robot 110. The sensor 126 may also determinethe direction from the robot 110 to the rollable object. The sensor 126may then calculate the location of the rollable object by using thelocation of the robot 110, the direction of the rollable object, and thedistance of the rollable object.

If the rollable object is located within the boundaries of thecollection area, the controller 318 is instructed to direct the robot110 to the rollable object and to collect the rollable object 620. Butif the rollable object is located outside of the boundaries of thecollection area, the controller 318 is instructed to continue scanningthe collection area with the sensor 622.

In some methods, the collection area may be divided into at least afirst collection sub-area and a second collection sub-area, with therobot 110 being located in the first collection sub-area. For example,if the collection area is a half of a tennis court, the collection areamay be divided such that the first collection sub-area is the backcourtof the half and the second collection sub-area is the frontcourt of thehalf. According to this method, when determining whether one of theplurality of rollable objects is located within the boundaries of thecollection area, it is also determined whether the rollable object islocated within the boundaries of the first collection sub-area. If therollable object is located within the boundaries of the first collectionsub-area, the controller 318 is instructed to direct the robot 110 tothe rollable object and to collect the rollable object. But if therollable object is not located within the boundaries of the firstcollection sub-area, the controller 318 is instructed to continuescanning the first collection sub-area with the sensor 126. Only afterthe first collection sub-area has been scanned, the controller isinstructed to direct the robot to the second collection sub-area.

As one skilled in the art will recognize, the collection area may bealternatively divided into more than two collection sub-areas. Bydividing the collection area into two or more sub-areas, the methodimproves the efficiency of the robot in the collection process. Therobot is able to more quickly collect the rollable objects and expendsless energy during the collection process.

D. Conclusions

It is to be understood that any given elements of the disclosedembodiments of the invention may be embodied in a single structure, asingle step, a single substance, or the like. Similarly, a given elementof the disclosed embodiment may be embodied in multiple structures,steps, substances, or the like.

The foregoing description illustrates and describes the processes,machines, manufactures, compositions of matter, and other teachings ofthe present disclosure. Additionally, the disclosure shows and describesonly certain embodiments of the processes, machines, manufactures,compositions of matter, and other teachings disclosed, but, as mentionedabove, it is to be understood that the teachings of the presentdisclosure are capable of use in various other combinations,modifications, and environments and is capable of changes ormodifications within the scope of the teachings as expressed herein,commensurate with the skill and/or knowledge of a person having ordinaryskill in the relevant art. The embodiments described hereinabove arefurther intended to explain certain best modes known of practicing theprocesses, machines, manufactures, compositions of matter, and otherteachings of the present disclosure and to enable others skilled in theart to utilize the teachings of the present disclosure in such, orother, embodiments and with the various modifications required by theparticular applications or uses. Accordingly, the processes, machines,manufactures, compositions of matter, and other teachings of the presentdisclosure are not intended to limit the exact embodiments and examplesdisclosed herein. Any section headings herein are provided only forconsistency with the suggestions of 37 C.F.R. § 1.77 or otherwise toprovide organizational cues. These headings shall not limit orcharacterize the invention(s) set forth herein.

I claim:
 1. A robot for collecting tennis balls capable of an uprightposition and a horizontal position, and having a midpoint between frontand rear, said robot comprising: (a) a front end; (b) a first axis ofrotation about which the robot rotates when tilted between the uprightposition and the horizontal position; (c) a first load-bearing wheelcapable of supporting the robot forward of the midpoint, having a radius(r), positioned so that the robot may be rotated at least 45° from thehorizontal position along the first axis of rotation without the frontend coming into contact with the ground and while the first load-bearingwheel remains in contact with the ground; (d) a mobile load-bearingsupport structure capable of supporting the robot while in thehorizontal position; (e) a drive motor providing rotation to a drivewheel; (f) a rotating collector proximate to the front end anddimensioned to collect the tennis balls; and (g) a holding basket havinga first basket position, in which said holding basket is positioned toreceive the tennis balls from the rotating collector while in thehorizontal position and in the first basket position.
 2. The robot ofclaim 1, comprising a controller connected to provide control signals tothe drive motor; and a sensor connected to provide data to thecontroller.
 3. The robot of claim 1, wherein the front end has a bottomsurface, and wherein the bottom surface has a clearance distance (C) atevery distance (h) in front of the first axis of rotation, such thatC≥h+r*[1−sqrt(2)] when in the robot is in the horizontal position. 4.The robot of claim 1 having a center of mass and a rear end, and whereinthe center of mass is between the midpoint and the front end when therobot is not loaded.
 5. The robot of claim 1, comprising an extendablechassis having an extended chassis position and a retracted chassisposition.
 6. The robot of claim 1, comprising an extendable chassishaving an extended chassis position and a retracted chassis position,and wherein the extendable chassis comprises a telescoping member. 7.The robot of claim 1, comprising a ramp positioned to receive the tennisball from the rotating collector and guide the tennis ball to theholding basket.
 8. A robot for collecting a rollable object and capableof assuming an upright position and a horizontal position, the robotcomprising: (a) means for propelling the robot; (b) means forcontrolling propulsion of the robot connected to provide commands to themeans for propelling; (c) means for locating the rollable objectconnected to provide data to the means for controlling propulsion; (d)means for collecting the rollable object; (e) means for storing therollable object positioned to accept the rollable object from the meansfor collecting; (f) means for supporting the robot and allowing therobot to move across a surface in a low-friction manner; and (g) meansfor reorienting the robot from the horizontal position into the uprightposition, wherein said means for reorienting the robot comprises a firstload-bearing wheel having an axis of rotation about which the firstload-bearing wheel rotates and about which the robot rotates at least45° while the first load-bearing wheel is in contact with the groundwhen tilted between the upright position and the horizontal position. 9.The robot of claim 8, wherein the robot has a height when in the uprightposition, comprising means to reversibly extend the height of the robotwhen the robot is in the upright position.
 10. The robot of claim 8,comprising means to elevate the means for storing when the robot is inthe upright position.
 11. The robot of claim 8, wherein the means forpropelling the robot comprises a drive motor, a battery connected tosupply power to the drive motor, and a drive wheel positioned to bedriven by the drive motor.
 12. The robot of claim 8, wherein the meansfor supporting the robot and allowing the robot to move across a surfacein a low-friction manner comprises a plurality of wheels.
 13. The robotof claim 8, wherein the means for controlling propulsion of the robot isan electronic controller.
 14. The robot of claim 8, wherein the meansfor locating the rollable object comprises a visual sensor.
 15. Therobot of claim 8, wherein the means for collecting the rollable objectis a rotating collector.
 16. The robot of claim 8, wherein the means forstoring the rollable object comprises a holding basket.
 17. The robot ofclaim 8, wherein the means for reorienting the robot further comprises asecond load-bearing wheel coaxial with the first load-bearing wheel. 18.The robot of claim 8, wherein the means for storing the rollable objectcan be positioned at an approximate hand level of a standing adult whenthe robot is in the upright position.
 19. The robot of claim 8, whereinthe means for storing the rollable object can be elevated to anapproximate hand level of an adult when the robot is in the uprightposition while leaving the means for reorienting the robot in contactwith the ground.
 20. The robot of claim 8, comprising a ramp positionedto receive the rollable object from the means for collecting and guidethe rollable object to the means for storing.